WASHINGTON, March 3 (Reuters) - and aircraft maker Airbus blamed each other on Wednesday for the second-worst air disaster in U.S. history - a 2001 crash that killed 265 people in New York.

American blamed the Nov. 12, 2001, crash on the plane's flight control system, while Airbus said the pilot was improperly trained.

Documents submitted by each company to the National Transportation Safety Board signaled that the government is close to finishing one of its most complex air crash investigations. It was also the agency's first probe involving the European-based Airbus.

The submissions also crystallize arguments the companies have been making piecemeal and in private since the Airbus A300-600 lost its tail fin over New York and plunged into a residential neighborhood near John F. Kennedy airport.

All 260 people on the American Airlines flight, bound for the Dominican Republic, and five on the ground were killed. The crash shook an already-traumatized New York City just two months after hijacked airliners slammed into the World Trade Center in the Sept. 11 attacks.

The American Airlines crash was the first time anyone could recall a tail fin and rudder snapping off a commercial plane, creating a mystery that has tested the most advanced theories on the effects of turbulence and aerodynamics on aircraft construction.

American said the design of the flight control system was unique and included an "unexpectedly sensitive" rudder, which caused co-pilot Sten Molin to lose control of the wide-body aircraft shortly after take off.

"What the pilots of Flight 587 did not know was that the rudder controls on the become increasingly sensitive as airspeed increases," American said.

Airbus blamed the crash on what it called "aggressive" rudder training by American, which it said led Molin to inadvertently mishandle the plane when he encountered turbulence from the wake of a bigger aircraft flying ahead.

"The (co-pilot) did exactly as he was trained to do with predictable fatal consequences," Airbus said.

American said it has found no connection between the airline's training and the crash.

Ted Lopatkiewicz, a safety board spokesman, said the American and Airbus conclusions on the crash would be considered by investigators. "But these are opinions, not factual reports."